This invention relates to a method and apparatus for destroying the needle portion of a syringe. In particular, the present invention relates to a method and apparatus that heats, sterilizes and severs the needle portion of a syringe after the needle has been used on a patient.
The threat of infectious diseases, in particular AIDS and hepatitis B, is very prevalent today in hospitals and doctors"" offices as a result of the use of hypodermic syringes. The Centers for Disease Control in Atlanta has extensively studied accidental syringe sticking incidents and have logged where most of the accidents occur and to whom. The Centers"" records indicate that nurses experience more incidents than most other medical personnel.
Recovering the needle after use, using the plastic tip cover provided with the syringe, is not an effective solution because a person may be stuck while attempting to place the cover on the needle. For that reason, medical professionals are prohibited from recapping syringes after use and instead must place used syringes in an approved disposal such as a sharps container. So-called safety needles having a slideable housing to cover the needle after use have been proposed, but have not found widespread acceptance.
The prior art includes the apparatus disclosed in U.S. Pat. No. 4,628,169, which describes an apparatus for melting only the tip of the needle, with the remainder of the metal on the syringe being detached by a separate operation. The remaining metal portion may still be contaminated. That apparatus still leaves the possibility of the person collecting the remaining needle portion being exposed to microorganisms. Also, any infectious fluids are still available to flow out of the now-open plastic portion of the syringe.
U.S. Pat. No. 4,877,934 discloses a needle destroying apparatus using converging electrodes to destroy the needle. However, the burnt needle tends to bend and lose contact with an electrode during operation, and the burnt needles tend to collect on the bottom electrode of that apparatus.
U.S. Pat. No. 5,736,706 discloses apparatus for removing syringe needles using a needle carriage that must be rotated from a loading position to a cut-off position to sever and remove the needle from the syringe.
What is needed is an improved needle removal apparatus that is easy to operate and will reliably remove and contain the needle without risk of sticking. What is further needed is an apparatus that can be used in a clinical environment for long periods of time without requiring disassembly for servicing or cleaning
Stated generally, the present invention is an apparatus and method for destroying a syringe needle by heating the needle to the melting temperature and simultaneously severing the needle from the plastic syringe. More particularly, the invention comprises a housing and a needle cartridge that receives a needle in a loading position. When a needle is inserted into the housing, the needle cartridge is retracted to a cut-off position. At the cutoff position, two opposing contact surfaces pinch the needle and electrically connect the needle to an electrical power source such as a battery. Current flows through the contact surfaces and the needle, thereby melting a portion of the needle. This retracting motion of the needle cartridge also causes the contact surfaces to sever the needle at the melted portion, so that the severed portion of the needle falls into a waste compartment in the housing. The apparatus preferably includes a layer of fire-retardant material that the needle penetrates to engage the needle cartridge, to prevent sparks from escaping the apparatus as the needle is melted and severed. When the syringe is removed from the needle cartridge, the needle cartridge returns to the initial loading position.
The needle cartridge is removable from the housing for suitable disposal after destroying a predetermined number of needles. The severed needle portions remain within the needle cartridge during and after such removal, and thus are not exposed to contact by the waste handlers. The replacement needle cartridge includes new contact surfaces for pinching and melting needles, so that the contact surfaces should not require servicing during normal operation.
It is therefore, an object of the present invention to provide a safe, low cost, efficient and easy-to-use device for sterilizing and destroying the metal needle of a hypodermic syringe, thereby killing any infectious microorganism that may be present in or on the needle.